Question: $ { {3} \times \left[\begin{array}{rrr}{1} & {1} & {3} \\ {3} & {-2} & {2}\end{array}\right] = {?} } $
Explanation: To multiply a matrix by a number, multiply each item of the matrix by the number. ${\left[\begin{array}{rrr}{3}\times{1} & {3}\times{1} & {3}\times{3} \\ {3}\times{3} & {3}\times{-2} & {3}\times{2}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{3} & {3} & {9} \\ {9} & {-6} & {6}\end{array}\right]}$